People have been using weighing scales for thousands of years, but only until recently have extremely accurate weighing methods been available. The original scales were developed to facilitate accurate commerce along major trading routes, which is still an important function today. Scales are now critical parts of the work of medical and scientific professionals.

Identification

Weighing scales are used to measure weight and/or mass of an object, reports the United States Department of Agriculture. Dozens of types of scales exist, but the simplest scale uses a beam and a pivot to balance the weight of one known object with another. More modern weighing scales use digital calibration to give a more accurate and quicker reading.

History of Weighing

People have needed to weigh objects, especially for trade, since the earliest known societies, claims Maths.org. Barterers had to determine how much food they required if they wanted to trade for construction materials. Around 1000 BC, societies in Asia and the Mediterranean acknowledged the need for a standardized weighing system. Stones were the first units of weight, according to Maths.org.

Commercial

An exact scale is critical for restaurants and other food industries that must portion food for sale. Meats, fruits and vegetables are usually sold by the pound; if you cannot correctly weigh an item the price per pound could vary widely from the actual weight. According to RestaurantReport, even at a profitable restaurant food costs around one-third of the total sale price. Labor and food can total 50 to 75 percent of total sales. Thus, even an error of only a few percentage points can have a large impact on a business's profit.

Health

A weighing scale is an essential component to maintaining the health of your body and measuring the progress of a growing child. The National Heart, Lung and Blood Institute uses a person's weight to calculate a Body Mass Index that can determine if you are under or overweight. To calculate BMI you divide your height in inches divided by total weight in pounds. An average BMI hovers in the 18 to 24 range.

Science

Chemists often deal with chemical equations that call for specific amounts of substances and different concentrations of solutions. If you wanted to make 1 gram of a 20 percent solution of sodium chloride (table salt), you would need to measure out 0.2 grams of NaCl and 0.8 grams of water, otherwise you cannot get an exact 20 percent solution.